Scorpion diversity and distribution in southern Africa: Pattern and process

Patterns of scorpion diversity and distribution in southern Africa (south of 15 degrees latitude), and the processes that produced them, are reviewed. A georeferenced presence-only dataset, comprising 6766 point locality records for the 140 scorpion species currently recognised in the subregion, is compiled and analysed with a geographical information system. Hotspots of scorpion species richness and endemism in southern Africa are mapped at the level of a quarter-degree square. The taxonomic composition of the southern African scorpion fauna is assessed and found to comprise distinct western and eastern components. Hotspots of species richness and endemism are concentrated in and regions with rugged topography, complex geology, or substratal heterogeneity. The distributions of genera and species are discussed in terms of their ecological requirements and modes of speciation within the context of historical events. Historical changes in the geomorphology and climate of southern Africa, coupled with the specific ecological requirements of most southern African scorpions, are proposed as primary causes for their speciation and, ultimately, their high species richness and endemism.